Yeah, I got the JamMan for Christmas to play around with at home. You'll need the footswitch too.
The days are too short for me to get into, so I'm waiting for Spring a little bit more before I really start playing with it.
Things I've got to learn with it are the exact loop segments of songs to record so that they can be strung together correctly. When you're in a loop and the loop hasn't completed, you can hit the footswitch and when the loop finishes it will instantly go to the next loop. So, you have the pre-played loops already stored and you can direct it around, even back to previous loops.